There are intrinsic limitations to learning about behavior associated with aging, health, and economic status when the data come from a single country. Public-sector pension and health-insurance plans are subject to meaningful variation only across countries, not within them. The overall objective of the External Innovative Network Core is to promote international collaborative research on health and economic status in older populations. This Core will allow RAND's Center for the Study of Aging to maintain and expand an international network of researchers and a research agenda on health and economic status in older populations. The network includes informal arrangements such as collaborations with the Mannheim Research Institute for the Economics of Aging and with the Institute for Fiscal Studies in London, as well as formal participation in a European Union-sponsored research training network on the economics of aging in Europe. It is anticipated that researchers involved in these collaborations will continue to generate and conduct research projects making international comparisons; to that end, the Core will provide limited research support to its European collaborators. The Core will support the efforts of RAND experts to assist and advise in the development of new international data gathering efforts, particularly the English Longitudinal Study of Ageing and the Survey of Health, Ageing and Retirement in Europe. The Core will allow the Center to organize conferences and workshops facilitating international comparative research by bringing together both international scholars from RAND and from other U.S. institutions. These meetings should be particularly useful in comparing measures and data from the U.S. Health and Retirement Study with those from the similar efforts in European nations, some of which have been established only recently. The Core will sponsor the attendance of international scholars at ongoing RAND institutes and workshops. Chief among these are the Mini-Medical School for Social Scientists and the Workshop on Aging, held in close proximity every summer. These two workshops allow researchers at all experience levels to learn from each other, but will be particularly useful to junior researchers whose travel opportunities are limited. A visiting-scholars program will be established for both short-term and sabbatical stays at RAND, for which the Core will fund travel and research support expenses (and, for the short-term stays, a stipend). There will be a complementary program of short stays by RAND scholars at foreign institutions.